This article focuses on participatory research to understand, support and promote the implementation of skills assessment in Cycle 3 within a strengthened priority education network. The research falls within the theoretical and methodological framework of ergonomic analysis of teachers’ activities in their workplace and is enriched by a didactic analysis aimed at identifying the knowledge in circulation related to the tools implemented in skills assessment. Analysis of the results shows that the evaluation systems and their use(s) are characterized by the (...) massive recourse to external resources, the time-consuming construction of new tools, and the enhancement of behavioural and cross-curricular skills to the detriment of disciplinary knowledge. The difficulty of establishing continuity in the students’ pathways due to different professional cultures and sometimes dissonant prescriptions between network primary and middle schools is obvious. The discussion questions the conditions of implementation of prescriptions relating to skills assessment and the articulation of ergonomic and didactic approaches within participatory research. (shrink)

The dynamics of calcium in the cortical cytoplasm of plant cells has been modeled by Goodwin & Trainor (1985) using a mechanochemical field theory based on the interaction between calcium ions and the cytoskeleton. The resulting mathematical model is a system of two non-linear partial differential equations which rule the evolution of the free calcium concentration and of the cytogel strain field in the cytoplasm. According to the values of parameters such as: calcium diffusion coefficient, strength of the calcium-strain coupling, (...) gel elasticity or total calcium concentration, this system may be stable or unstable around an homogeneous equilibrium state. With the aid of numerical simulations, various kinds of solutions have been observed. When inertial forces ar neglected or for low values of the gel density, most of the solutions are asymptotically stable and are reached after a more or less complex transient. But for higher values of the volumetric density more complex solutions may exist, periodic in time and space or eventually chaotic. (shrink)

S'intéresser au concept de 'catégorie' dans la philosophie d'Aristote c'est se pencher sur l'un des objets qui a le plus suscité de commentaires depuis l'Antiquité jusqu'à la modernité récente -- de Porphyre à Derrida en passant par les stoïciens, Alexandre et les philosophes arabes. Loin d'être limitée au traité qui a porté ce titre ("Des catégories"), traité dont l'objet et le sens même font difficulté, la kategoria se situe à la croisée des divers champs de questionnements philosophiques aristotéliciens et des (...) enjeux de la physique, de la logique, de la dialectique et de la science 'première'. L'objet de ce volume est d'éclairer, à partir de quelques-unes des lectures actuelles et des grandes approches interprétatives, les difficultés majeures d'interprétation que le concept de 'catégorie' (kategoria) a posé à la tradition, ainsi que d'en renouveler la compréhension à même les textes." -- Back cover. (shrink)

The growth of the vein system of the leaf ofTropaeolum peltophorum was studied at the vein level and at the limb level.The vein growth kinetics depend on the position of the vein on the leaf: there is a proximal/distal gradient and a bilateral gradient of the growth parameters. The growth field of the veins is also dependent on time and on vein position.Specific correspondences exist between singular points of the global growth curves, the variations of the growth field and the (...) vein position. The spatio-temporal organization of the vein system growth is then characterized by positional variations of kinetic order which show the existence of areal morphogenetic dissymmetry. (shrink)

The growth of the vein system of the leaf ofTropaeolum peltophorum was studied (i) at the vein level (analysis of the growth kinetics and of the growth field of the 7 primary veins) and (ii) at the limb level (comparison of the growth of the veins).The vein growth kinetics depend on the position of the vein on the leaf: there is a proximal/distal gradient and a bilateral gradient of the growth parameters (=variation of the temporal organization of the kinetics). The (...) growth field of the veins (=local growth pattern) is also dependent on time and on vein position. (shrink)